Contents described herein provide only background information of embodiments but do not constitute prior art.
In general, a semiconductor memory device, a liquid crystal display device, an organic light emitting device, etc. are fabricated by depositing and stacking structures of a desired shape by repeating a semiconductor process on a substrate a plurality of times.
Semiconductor fabrication includes a process of a depositing a designated thin film on a substrate, a photolithography process for exposing selected regions of the thin film, an etching process for removing the thin film from the selected regions, etc. Such semiconductor fabrication is carried out within a reaction chamber in which optimal conductions for the corresponding process are realized.
The substrate deposition process is executed using chemical vapor deposition (CVD) or atomic layer deposition.
In CVD, since a deposition film is formed on a substrate by injecting process gas for deposition onto the substrate, CVD has high deposition speed but has low uniformity and quality of the deposition film, as compared to atomic layer deposition.
In atomic layer deposition, since a deposition film is formed on a substrate through atomic layer adsorption by sequentially injecting source gas, purge gas, reaction gas and purge gas onto the substrate, atomic layer deposition is advantageous in that the deposition film is uniformly deposited on the substrate but has low deposition speed.
As high integration of devices formed on a substrate and production of a substrate having a 3D structure are required, the substrate deposition process requires formation of a deposition film having uniform and high density and high uniformity in deposition, i.e., high step coverage.
Particularly, if a gap-filling process for filling gaps formed on a substrate having a 3D structure by stacking a plurality of deposition films during production of the substrate is executed, undesirable voids may be generated in regions where the deposition films are combined integrally.
Since generation of such voids causes defects in operating characteristics of a semiconductor product, semiconductor products having voids should be discarded and, thus, a substrate processing method for reducing generation of voids is required.